What conditions should a qualified lithium battery meet in terms of safety performance?

Safety features of lithium batteries: Regarding the testing policies for the safety performance of lithium batteries, international rules are very strict standards. A qualified lithium battery should meet the following conditions in terms of safety performance: (1) Short circuit: no fire, no explosion (2) Overcharge: no fire, no explosion (3) Hot box test: no fire, no explosion (constant temperature of 150°C for 10 min) (4) Needle stick: no explosion (3 mm Ф penetrates the cell) (5) Plate impact : No fire, no explosion (10kg weight falls on the battery from a height of 1 meter) Advantages of lithium batteries: (1) The working voltage of the high-voltage single battery is as high as 3.7-3.8v (lithium iron phosphate 3.2v), which is nickel-hydrogen nickel 3 times that of cadmium batteries. (2) The actual specific energy is about 555Wh/kg, that is, the material can reach a specific capacity above 150mAh/g (3-4 times ni-cd, 2-3 times ni-mh), which is close to its theoretical value Around 88%. (3) The long cycle life can reach more than 500 times, even more than 1000 times, and the lithium iron phosphate can reach more than 2000 times. Regarding low-current discharge appliances, battery life will be doubled as competitive appliances. (4) Good safety function, no pollution, no recall effect. Li-ion's predecessor new lithium battery, lithium battery, easy to form metal lithium dendritic short circuit, reducing the application: Li-ion environmental pollution without cadmium, lead, mercury and other elements: some processes (such as sintered type) Ni-Cd batteries actually face a major disadvantage, severely restricting the use of batteries, but there is no such problem in Li-ion roots. (5) The self-discharge rate of lithium ion after 1 month storage at room temperature is about 2%, which is much lower than the 25-30% of nickel-cadmium and 30-35% of nickel-hydrogen. Fast charging 1C charging can reach more than 80% of the nominal capacity in 30 minutes, while the ferro-phosphorus battery can reach 90% of the nominal capacity in 10 minutes. (7) Working temperature The working temperature is -25~45℃. With the improvement of electrolyte and positive electrode, it is expected to be widened to -40~70℃. (6) Burning: non-explosive (gas flame grill battery) Lithium battery defects: (1) Aging: unlike other rechargeable batteries, the capacity of lithium batteries will decrease with the number of uses and temperature changes. This expansion can be represented by a decrease in volume or an increase in internal resistance. Due to the temperature, the performance of electronic products with larger currents is relatively short in operation. Replacing graphite with lithium titanate seems to extend its life. The relationship between storage temperature and permanent loss rate of capacity: (2) Recovery rate: For various reasons, about 1% of new products have to be recycled. (3) Intolerance of overcharging: In the process of overcharging, the embedded excessive lithium ions will be permanently fixed in the crystal lattice and can no longer be released, resulting in a short battery life. (4) Intolerance of overdischarge: In the process of overdischarge, the electrode is deintercalated by too many lithium ions, which causes the lattice to collapse and shorten the service life. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Is the number of charge and discharge cycles the more the better?